Apologies if this has been discussed in another thread - the search feature wasn't very helpful.

Yeah, it doesn't work all that well. Google does a good job of indexing the site though so one option for searching is to use the site syntax in Google to search Appleinsider. For example, if you type in:

site:forums.appleinsider.com mac mini

Google will only return threads on Appleinsider about the Mac Mini and do it much quick than the internal search.

It depends on the resolution you choose. I'd expect 720p to playback ok but 1080p might not. It's not really dependent on the GPU because Flash isn't hardware accelerated on that model so all the decoding happens on the CPU.

With Youtube you get the HTML 5 option though and this plays back using half the CPU power under 10.6.

If you can, get the one with the 9400M, not the GMA because the 9400M is supported by the new Flash hardware acceleration not to mention OpenCL is supported should there be any future software update that uses it. All Apple's refurbs should have the 9400M.

Definitely avoid the old Macbooks with the 80GB drives because those HDDs were sloooow.